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Rossco

G60 cooling issues

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Been trying to get the rad sorted and its almost done, it runs really well now and im pretty happy but its not to happy with its cooling?? I ran it yesterday but it appeared the water pump was mashed, so that was changed today and it was filled up, heater on hot and i would fill, run, top up, run and so on till it seemed happy enough. Let it run for a while and the water light was flashing but the water was at the top of the bottle and its was coming back through the return, so i let it run. It ran fine for long enough, the oil temp was getting to about 60-70 degrees but the needle on the water guage didnt move, then my old man shouted me to turn the car off cos it had boiled over so i did.

 

we checked the hoses and the radiator, the top hose was roasting, the rad was freezing and so was the bottom hose.

 

Questions

 

Is my water bottle mashed??

 

Its a new thermostat in the water pump, could it be the cause of excessive cooking and no water access to the radiator?

 

The black sender beside the blue one is the sender for the temp guage on the dash?? Is mine broken or did it not get up to temperature enough??

 

Cheers for the help guys, this is pretty much all i need to know to get my G60 rolling

 

Ross

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my water pump went and replaced the stat with it spent ages on it and changed the water pump in the end from VAG twice than got the air locks out and it was fine....dunno if its worth checking ur new water pump and stat might not be 100% might be a common fault or its jus me unlucky...

 

does sound like u got a fat airlock in the top hose though,, when u filled up the water did u do it thru the top hose or water bottle???

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Filled it through the bottle, always have done, im goin on the assumption that the stats a dodgey one, ill boil it up in a pan in the morning and see, any ideas on the temp guage??

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Filled it through the bottle, always have done

 

Me too, as long as you fill it slowly and run it up to temp with the cap off...

 

If you do this - You should see the fluid level frop slightly as the stat opens

 

Not sure about the sensor readings, maybe you do have airlocks - I would change all the sensors anyway including the rad thermoswitch as thy are cheap and prone to failure!

 

May be worth doing a drain and refill and keep a close eye on this - this will tell you if you have a duff stat.

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you should always fill the coolant system from the top hose or you are VERY likely to get an air lock in the radiator or block. Anyway, change the blue and black sensors (will cost less than £30 from GSF and will probably sort out the temp gauge problem) and change the fan switch (big brass one on the radiator) just to make sure your fan will come on when it gets to temperature... ;)

 

Did you have the cap off the tank while you tried to run it up to temp? If you did, then that's part of your problem. The system NEEDS to be under pressure, as this ups the boiling point of the coolant and means that it won't boil. That's part of the reason you get problems with overheating due to a leak, it can't pressurise properly and so the boiling point drops screwing up the coolant efficiency.... :|

 

You may also want to change the coolant tank (use a Genuine one as the ones from GSF and Euro are utter crap) and coolant tank cap too so you can rule those out of the equation too...

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you should always fill the coolant system from the top hose or you are VERY likely to get an air lock in the radiator or block. Anyway, change the blue and black sensors (will cost less than £30 from GSF and will probably sort out the temp gauge problem) and change the fan switch (big brass one on the radiator) just to make sure your fan will come on when it gets to temperature... ;)

 

Did you have the cap off the tank while you tried to run it up to temp? If you did, then that's part of your problem. The system NEEDS to be under pressure, as this ups the boiling point of the coolant and means that it won't boil. That's part of the reason you get problems with overheating due to a leak, it can't pressurise properly and so the boiling point drops screwing up the coolant efficiency.... :|

 

You may also want to change the coolant tank (use a Genuine one as the ones from GSF and Euro are utter crap) and coolant tank cap too so you can rule those out of the equation too...

 

I took the top hose off and filled it up through the radiator, im gathering that this is wrong :oops: I also left the cap off all the time it was running, so im guessing that maybe the water boiled over before the temp guage could work?? the oil was only at 68 degrees.

 

So i take the top hose off and fill it that way?? Right ill give that a spin, ive also binned the thermostat for the mo just to make things easier.

 

Cheers guys ill let you know how i get on

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either way from the top hose should be fine... the problem with filling from the expansion tank is that it will fill from the middle, not top/bottom of the coolant system so you enhance the chances of getting airlocks... ;)

 

The water will get hotter faster than the oil when it's not pressurised...

 

G60 Jet look at the diameter of that pipe compared to the diameter of the pipe you're putting the water in through and you'll see precisely why you get air locks filling it up from the tank... ;) With the top hose off the rad, you have the same size pipe to let the air out which helps stop airlocks... ;)

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Heres something, when i filled it through the radiator, furki said the water would come through the top hose and that would be it full but it never, any ideas as to why it didnt or was the boy furki getting mixed up??

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Henny, not if you poor it in slowly!! the tank pipe is smaller than the cooling system hose too

 

Thjats how i've done it 3 times now altho Henny's way is fairly full proof I think it's only really necessary on the VR6 with it's various waterways...

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It's not just the VR, but most engines. The proper VW technique is via the rad top hose. The reason being as Henny said is because pouring it in through the expansion tank introduces air as the coolant goes down. Pouring it in through the top hose forces air out of the block/head from the bottom up.

 

So.....

 

In via the top hose until you see coolant appear in the expansion tank.

Refit top hose.

Run the engine with the expansion cap OFF.

When the stat opens the water will start to rise in the tank, NOW you screw the cap on to pressurise the system.

Drive car for 20 mins or so.

Top up in the morning or when cold again.

 

That's what VW and Stealth do and works everytime.

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Heres something, when i filled it through the radiator, furki said the water would come through the top hose and that would be it full but it never, any ideas as to why it didnt or was the boy furki getting mixed up??

 

fill through the top hose and once its full "there" connect the hose up and slowly fill through the expansion bottle till it gets full,,,,,,,,, :lol:

 

been a while since i did it

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Guys,

 

i managed to mess up the replacement of my coolant by pouring it through the expansion tank. now it either runs cold or too warm.

 

Whats the best possible solution for this??

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